Method for producing multiple electron discharge devices



S. LOEWE Feb. 5, 1935.

I METHOD FOR PRODUCING MULTIPLE ELECTRQN DISCHARGE DEVICES Filed June 12, 1950 Jpken/or:

Patented Feb. 5, 1935 v i UNITED .STATES'aPATEN METHOD FOR PRODUCING MULTIPLE ELECTRON DISCHARGE DEVIGES Siegmund Loewe, Berlin, Germany Application June "12, 1930; serial 1x16460573 In Germany June 7,1929

3. Claims. (01. w -27.5)

. The invention relates to high emission tubes be reached simultaneously in the two anodal to be used asamplifying, as rectifying and as systems." transmitting valves. Such high emission valves The solution of the problem as above described, are', for instance,'manufactured at present by the i. e. a suitable choice of the heating and radiating 5. metal vapour process. For this purpose a light conditions of the two anodal systems, however, li:

metal, usually barium, isatomized in the vacuum means a considerable restriction in respect of anddeposited on the cathode'surface which, if dimensioning the two amplifier systems. The necessary, has been prepared beforehand. In the multiple tube may, for instance, consist of a case of. simple tubes this method entails no difli powerful terminal (end stage) system and a priculty. The anode is used as a carrier for the submary stage which is'to act as voltage amplifier. 1 a: stance to be evaporated. When this anode is The multiple tubes may contain coupling elements sufiiciently heated, the barium will be caused for connecting the systems; but my invention is to evaporate. The barium is produced either not limited to'such kinds of multiple tubes. The from barium acetate or from a reaction compound terminal stage is in practice appropriately adwhichmay consist, for instance, "of barium oxide justed to a medium emission of 50 milliamperes, lol and silicon. J while in the other system'the emission of the The method will, however, be unsatisfactory filament is of the order of only one tenth milliif'ina common vacuum more than one cathode ampere; In this 'connection'great practical diffisystem is'to be coated. Theobject may, for inculties would arise 'ifiboth anod'estwere to be stance be to produce by the vapourprocess the dimensioned according to the above principle. 20 filaments of a double tube with two equal ampli- The an'odeof the voltage stage more particularly fier systems, i. e. each consisting of cathode, grid would have to be made unnecessarily large; and anode. In this connection I have found Therefore, according to my invention, the subtha't,'in order that the tube may be successfully stances to be evaporated are arranged in such manufactured, it is essential that the systems a way'that'by heating a single system the coating should be ofidentical construction, so that the substances for all the systems are vaporized. evaporation'of the barium in both systems takes "My 'inventionwill be best understood with sea place at the same time. Ifsuch is not'the case, erence to the accompanying drawing in which i i. erif the barium in one system evaporates before Fig. 1 shows a double valve, Figures 2 and 3 evaporating in. the other'one, the quantities of a triple'valve according to my invention. f bariumpr'ecipitated first in the hotter system "A' po'cke't in which the reaction for producing will be affected by the inevitable discharge of barium may 'take place (Goldschr'nidts reaction), gas preceding the evaporation of the barium in is shown on a larger scale in Fig. 4. Thispock-et the other system. This results in an unequal of Fig. 4 corresponds to the pockets 5 and 9 of deposition of barium on the two'systems. Figures 1 and 3, and to the pockets 5, 9 and 10 of 333 The problem of producing multiple tubes by Fig.2. the evaporation process may, according'to the in- In Fig. 1 l is the cross-section through the vention; be solved by the various anodes 'arglass'bulbof a two stage (double)-amplifier tube. ranged in the tube being made of such dimensions 2.is the cross-section through the oval-cylindri- 40 that under the influence of a common eddy curcal anode (plate) of the terminal power stage. 3 rent'field, effecting the glowing of the anodes, indicates bydashes the grid (controlling electhe temperature of the anode systems rises evenly trode) ,4 the cathode (filament) At '5 a pocket inv such a manner that the barium evaporation in is folded in the anode which pocket, as indicated both systems takes place at the same time. In by hatching, contains the barium. reaction comcarrying out these operations I have found that pound. Upon the glowing of the anode 2 the 453 it is sufficient for the requirements in practiceif barium is liberated, evaporates into the inner anthe'cro'ss-sections of the two anodal systems are can spaceand there precipitates on the filamade equal in the direction of the eddy current ment 4. field. Physically it is, of course, only necessary The voltage p fi System consists, for

for the heat quantities generated in the two stance, of the anode the d d the Cat d 50 anodal systems and for their radiating ratios 8. In order to form this cathode 8 also by the to be selected so that the rise of temperature in metal vapour process, a. further pocket 9 is, acthe two anodes takes place at the same time with cording to the invention, provided at the anode the same strength in order that the temperature 2, which pocket, however, while being also filled zone of 1000" necessary for the evaporation may with the reaction compound, opens up to the out- 55 side in order to allow the discharging barium metal vapour to precipitate upon cathode 8. The action is not affected if the anode 6 has a higher or lower temperature than anode 2, as it may easily be arranged that at the points where the pockets 5 and 9 are situated the evaporation temperature of barium is reached at the same time. In order to illustrate the process, I have indicated by arrows starting from the two pockets the direction into which the vapour of the barium will go.

At the same time the invention shows a further advance. It is known that cathodes produced by the metal evaporation process sometimes lose in their efiiciency. This loss, however, does not occur, if a residue of the vaporizable substance has remained in the cathode and if the anode either under operating conditions or by occasional overloading is subjected to such an increase of temperature that a continuous, though only weak evaporation of the stored barium takes place. It is obvious even if a residue of barium had remained in the anode 6 of the voltage stage, that then owing to the extremely small load of such anode no increase of temperature of the same and therefore no further evaporation would take place. If, however, the metal vapour source for the voltage amplification stage is arranged directly at the power anode 2, upon the overloading of such anode or upon strong operative loading of the same a permanent additional evaporation of the barium will take place by which the voltage stage which remains in itself cold and unloaded will also profit.

In Fig. 2 a small modification is shown where more than one primary or initial stage is produced in the same manner. The designations have the same meaning as in Fig. 1, there being, however, a pocket 10 in addition to pocket 9 and a further system 11, 12, 13 in addition. to the system 6, '7, 8, the additional system being treated in the same manner as described above.

Fig. 3 shows a somewhat difierent form of construction in which the barium vapour developed in the pocket 9 feeds not only a single initial stage consisting of the anode system 6, '7, 8, but in the same direction a further initial stage consisting of the system 14, 15, 16.

Naturally the invention may be put into practice in many forms of embodiments. Thus, for instance, the vapour may be passed axially in lengthwise direction through cylindrical systems. Likewise the barium source may be taken for a large number of different systems from a single heatable metal mass which need not necessarily be an anode or generally an electrode of the amplifier systems.

Generally speaking the second way of solving the problem of my invention consists in coating several cathodes belonging to different discharging systems with a highly emissive layer from a common support carrying the barium substance which support has been heated.

For electrical reasons it may be necessary to arrange static screens between the anode of the terminal stage 2 and the further amplifier systems. This may, for instance, be done as indicated on Fig. 1 by a metal sieve 17 being provided between the anode 2 and the system 6, 7, 8. This sieve is connected with any point of constant potential, e. g. the negative end of the heat ing filament. The barium vapour may pass the sieve without diificulty. Electrically, however, it represents a sufficient screen. Similar grid screens 17 are arranged in Figure 3 between the systems 2, 3, 4 6, '7, 8 and 14, 15, 16.

What I claim is:

1. A multiple valve comprising several electrode systems, each electrode system consisting of a plate, a grid and a cathode coated with a highly emissive barium layer, one of the anodes of said electrode systems being provided with pockets for containing the reaction compounds from which the highly emissive barium layers of the cathodes may be produced, the pocket for containing the barium compound for coating the cathode of the system belonging to said anode being opened to the inside of said system, the pocket containing the barium compounds for coating the cathodes of the other electrode systems being opened towards these other electrode systems, said other electrode systems having no anode-portion between its cathode and the pocket for containing the reaction mixture for coating said cathode.

2. A multiple valve comprising several electrode systems, each electrode system consisting of a plate, a grid and a cathode coated with a highly emissive barium layer, one of the anodes of said electrode systems being provided with pockets for containing the reaction compounds from which the highly emissive barium layers of the cathodes may be produced, the pocket for containing the barium compound for coating the cathode of the system belonging to said anode being opened to the inside of said system, the pocket containing the barium compounds for coating the cathodes of the other electrode systems being opened towards these other electrode systems, said other electrode systems having no anode-portion between its cathode and the pocket for'containing the reaction mixture for coating said cathode, and a sieve-shaped screen arranged between said pocket and said electrode systems and adapted to be connected to a suitablev potential.

3. A multiple valve comprising several electrode systems, each electrode system consisting of a plate, a grid and a cathode coated with a highly emissive earth' alkaline' metal layer, one of the anodes of said electrode systems being provided with pockets for containing the reaction compounds from which the highly emissive layers of the cathodes may be produced, the pocket for containing the earth alkaline metal compound for coating the cathode of the system belonging to said anode being opened to the inside of said system, the pocket containing the earth alkaline metal compounds for coating the cathodes of the other electrode systems being opened towards these other electrode systems, said other electrode systems having no anode-portion between their cathodes and the pocket containing the reaction mixture for coating said cathodes.

SIEGMUND LOEWE. 

